Stable aqueous dispersions of cationic dyestuffs

ABSTRACT

Stable aqueous dispersions of cationic or anionic dyestuffs which are, per se, water-soluble, which dispersions contain a stabilizing agent in an amount of up to about 15 percent of their weight, the balance consisting of (a) water and, dissolved in the latter, (b) an at least sparingly water-soluble salt consisting of the anion of an inorganic or organic acid and of the cation of an inorganic base, and, in the case of said dyestuff being cationic, (c) acid selected from inorganic and organic acids, the pK values of which acids are at most 4.8, the concentration of the said salt in the water being high enough to keep the dyestuff practically undissolved.

United States Patent [1 1 Related U.S. Application Data Continuation ofSer. No. 781,610, Dec. 5, 1968, abandoned, which is acontinuation-in-part oPSer. No. 575,513, Aug. 29, 1966, abandoned.

Foreign Application Priority Data Dec. 8, 1967 Switzerland 17284/67 June10, 1966 Switzerland 8417/66 References Cited UNlTED STATES PATENTS12/1962 Bann et al 8/79 Bossard et al. Nov. 6, 1.973

[54] STABLE AQUEOUS DISPERSIONS OF 3,346,322 10/1967 Finkenauer et al...8/177 X CATIONIC DYESTUFFS 3,352,624 11/1967 Harding et al. 8/15 [75]Inventors: Werner Bossard, Riehen;'Frangois OTHER PUBLICATIONS Favre,Basle, both of Switzerland 73 A I Ch G AG B l S l d Vickerstaff,Physical Chem. of Dye, 1954, p. l8, l9. 2 t

[ 1 sslgnee I elgy as Zer an Diserens, Chem. Techn. Of Dye & Print,1951, p. 90, [22] Filed: Aug. 25, 1971 91.

21 Appl. No.: 174,964

Primary Examiner-George F. Lesmes Assistant Examiner-Patricia C. lvesAttorneyWenderoth, Lind & Ponack [57] ABSTRACT ionic, (c) acid selectedfrom inorganic and organic acids, the pK values of which acids are atmost 4.8, the concentration of the said salt in the water being highenough to keep the dyestuff practically undissolved.

6 Claims, No Drawings STABLE AQUEOUS DISPERSIONS F CATIONIC. DYESTUFFS-This application is a continuation application of Ser. No. 781,610,filed Dec. 5, 1968, now abandoned, which in turn is acontinuation-in-part application of Ser. No. 575,513, filed Aug. 29,1966, also abandoned.

This invention relates to new stable aqueous dispersions of cationic oranionic dyestuffs; it also concerns a process for thedyeing and printingof organic materials, especially fiber materials, with the aid of suchnovel aqueous dispersions.

According to a first aspect of the invention, concen-. trated stableaqueous dispersions of cationic dyestuffs (also termed color salts) areprovided which are particularly suitable for the dyeing and printing ofpolymeric and copolymericacrylonitrile fiber materials.

It is known that, in general, cationic dyestuffs are particularlysuitable to attain fast dyeings on polymeric or copolymericacrylonitrile fiber material. Up to the present, most of these cationicdyestuffs have been offered to the industry in the form of very dustypowders. However, working with such very dusty dyestuff powders, whichmoreover, generally have very high color strength, means that specialprecautionary measures have to be taken. For example, personnel have towear dust masks which are uncomfortable and often unhygienic, or costlyventilation systems must be installed.

As another drawback, very finely milled dyestuff powders have a greattendency to form lumps on storing in a moist atmosphere. Also, it isoften difficult to dissolve pulverulent cationic dyestuffs in water asthey do not wet well and form lumps on the addition of water. This makesthe preparation of dye liquors more difficult and, often, verytime-consuming. There is a need, therefore, in the dyeing industry, foravoiding these disadvantages as much as possible.

Various suggestions to this end havealready been made. It has beenrecommended that cationic dyestuffs should be offered commerciallyin'the form of concentrated solutions which contain substantial amountsof organic solvents. However, these solutions of cationic dyestuffs havevarious disadvantages. They easily dry up on being stored open-Also,such concentrated solutions of cationic dyestuffs, particularly whenthey are exposed to great variations in temperature,involve the dangerthat the'dissolve'd dyestuffs may crystallize 'out in the form ofrelatively coarse crystals when the ambient temperature decreases. Onprolonged storing, such. crystals will grow further, whereby thedyestuff content of the solutions is reduced so that an exactreproduction of dyestuff charges of a given composition in successivedyebaths is made difficult. Therefore, uneven dyeings or spotformationeasily occur on dyeing with such partially crystallizedsolutions.

According. to a first aspect of the invention, novel aqueous dispersionsof cationic dyestuffs of concentrated liquid consistency have been foundwhich are substantially free from the disadvantages listed above.

These novel stable aqueous dispersions have, as acharacteristic'feature, a-content of a. at least percent and at mostpercent, calculated on the total weight of the dispersion, ofwatersoluble cationic color salt;

- b. from about 1 to 5 percent by weight of the total dispersion, ofacid selected from those inorganic and organic, monobasic and polybasicacids, the pK value of which does not exceed 4.8 (measured at roomtemperature; cf. pages D and D91 of the Handbook of Chemistry andPhysics 48th Edition); 0. about 0.5 to 15 percent by weight of the totaldispersion, of stabilizer selected from cationic stabilizer andnonionogenic stabilizer, the balance of said dispersion consisting of d.water and, dissolved in the latter, e. water-soluble salt consisting ofthe anion of an inorganic or organic monoor polybasic acid the free acidof which has a pK value of at most 4.8 (as defined supra) and of thecation of an inorganic monoor polyacid base the free base of which has apK value of at most 4.8 (at 2025C, see page D89 of the Handbook, supra),the saltconcentration being high enough to keep the watersolubledyestuff substantially undissolved.

The anions of water-soluble salts usable according to this aspect of theinvention are derived principally from inorganic monoor polybasicmineral acids, e.g., from hydrochloric acid, hydrobromic acid, nitricacid or from sulfuric acid. They can also be derived, however, fromorganic monoor polybasic, optionally substituted carboxylic acid. Assuch can be used, chiefly, lower, optionally substituted, e.g., hydroxylsubstituted, aliphatic monocarboxylic acids, lower aliphatic diandtricarboxylic acids optionally substituted by hydroxyl groups, andmono-cyclic-aromatic monocarboxylic acids. Suitable anion donors are, inthe case of lower fatty acids, e.g., formic, acetic and glycolic acid;in the case of unsubstituted dicarboxylic acids, e.g:, oxalic, malonic,succinic, maleic, fumaric, glutaric and adipic acid; in the case ofdiand tri-carboxylic acids substituted by hydroxyl groups, e.g.,tartaric and citric acid. Suitable anions of mononuclear aromaticcarboxylic acids are, e.g., those of benzoic acid, chlorobenzoic acid,methylbenzoic acid and salicylic acid.

' Alkali metal ions such as sodium or potassium ions, alkaline earthmetal ions such as magnesium, calcium or zinc ions and also aluminiumions can be used as cations of water-soluble salts usable according tothis invention aspect.

As water-soluble salts of inorganic and organic polybasic acids,-alsotheir acid salts can be used according to the first aspect of theinvention. The neutral salts, however, are-preferred. Examples ofsuitable inorganic salts are, in particular, the neutral alkali metal orammonium salts of strong, inorganic, monoor di-basic acids such assodium, potassium and ammonium chloride; sodium, potassium and ammoniumbromide; so-

dium, potassium and ammonium nitrate; sodium, potassium and ammoniumsulfate or mixtures thereof; examples of suitable salts of organic acidsare, in particular, the alkali metal salts of lower fatty acids, chieflysodium and potassium acetate.

The cationic dyestuff is stabilized in the aqueous concentrate by thenecessary content of the dye preparation defined above of an inorganicor organic, monoor polybasic acid having a pK value of at most 4.8. The

acid content is advantageously so chosen that the con centrated liquiddye preparation has a pH of 2 to 5.

Suitable inorganic acids usuable according to the invention are, inparticular, mineral acids such as hydrochloric acid, hydrobromic acid orsulfuric acid. Advantageously, however, organic acids, particularlylower aliphatic carboxylic acids such as formic acid and, chiefly,acetic acid, are used.

In addition, dye preparations according to this invention aspect containat least one cationic or, preferably, a nonionogenic stabilizer. Ascationic stabilizers, amines are used, principally polyamines containingtwo or more basic nitrogen atoms, preferably two to five partially orcompletely quaternized nitrogen atoms, a polyglycol ether chain and atleast one lipophilic substituent. By polyamines are meant, inparticular, polyalkylene polyamine compounds the alkylene component ofwhich preferably consists of l,2-ethylene or of 1,2- or 1,3-propylenegroups, i.e., for example, diethylenetriamine, triethylenetetramine,tetraethylenepentamine or dipropylenetriamine compounds. One nitrogenatom of these polyamines has, as lipophilic substituent, an alkyl,alkenyl or acyl radical having, particularly, to 20 carbon atoms.Examples of such radicals are the tetradecyl, hexadecyl, octadecyl,eicosyl or the oleyl, myristoyl, lauroyl, palmitoyl, stearoyl, oleoylradical. Polyglycol ether chains in the polyamines usable according tothe invention contain 3 to about 100, preferably however, about 10 to50, alkyleneoxy groups, mainly ethyleneoxy groups of which a few can beC-alkyl or C-aryl substituted. PermethylatedN-octadecyldiethylene-triamine, for example, is mentioned as aparticularly suitable compound which has been reacted with toequivalents of ethylene oxide.

Particularly suitable non-ionogenic stabilizers are surface activeethyleneoxy adducts of organic hydroxyl, carboxyl, amino or amidocompounds containing aliphatic hydrocarbon radicals of, in all, at leasteight carbon atoms, or mixtures of such substances. They are obtainedwhen at least three equivalents and, preferably, more ethylene oxide areadded; substituted epoxides such as styrene oxide and propylene oxide,can be individually built in. Starting materials are higher fattyalcohols, i.e., alkanols and alkenols having eight to 20 carbon atoms,fatty acids having eight to 20 carbon atoms, alkylphenols having one ormore alkyl substituents containing in all at least eight carbon atoms,primary or secondary monoor polybasic amines containing aliphatic and/orcycloaliphatic hydrocarbon radicals having at least eight carbon atoms,particularly alkanolamines having such radicals, also alkariolamides,aminoalkylamides and aminoalkyl esters of higher aliphatic carboxylicacids and higher alkylated aryloxy carboxylic acids. The number ofalkyleneoxy' groups in these polyglycol ethers should give themhydrophilic properties and it should be so large that the compounds canat least be easily dispersed in water and, preferably, are solubletherein. Depending on the type and composition of the lipophilic component of these compounds, the number of alkyleneoxy groups, principallyethyleneoxy groups, should be 3, particularly 5 up to about 100 and,preferably 5 to 20. The use of technical mixtures of these substances isparticularly favorable.

Particularly valuable dispersions according to this invention aspectcontain, as stabilizers, polyglycol ethers from alkanols, alkenols andalkyl phenols which contain aliphatic hydrocarbon radicals having, inall, at least eight carbon atoms, and at least 4 equivalents of ethyleneoxide. Addition products of 4 to- 20 mols of ethylene oxide to analkanol having eight to 18 carbon atoms such as hexadecanol, the fattyalcohol mixture known by the generic term coconut oil fatty alcohol, oran alkyl phenol the alkyl radicals of which have, in all, at least eightcarbon atoms, e.g., an octyl phenol,

nonyl phenol or di-tert.butyl phenyl are particularly favorable.

As other auxiliaries, the dispersions according to this aspect of theinvention contain, optionally, condensation products of naphthalenesulfonicacids and formaldehyde; up to about 10 percent by weight ofthickeners such as locust bean flour, alkyl celluloses or crystal gum;up to about 1 percent by weight of antifoam agents such as higher fattyalcohols or higher molecular fatty acid esters. The dispersions can alsocontain antigelling agents or textile finishing agents, such as antisoilor antistatic agents or softeners.

As cationic color salts, the dispersions according to this inventionaspect contain the usual salts and double salts, e.g., metal halidedouble salts such as zinc chloride double salts, of cationic dyestuffsof the most varied classes, in particular, salts of methine orazamethine dyestuffs which contain a cyclammonium group, e.g., anindolium, pyrazolium, imidazolium, triazolium, tetrazolium, oxdiazolium,thiodiazolium, oxazolium, thiazolium, pyridinium, pyrimidinium,pyrazinium group. The heterocyclic compounds mentioned can optionally besubstituted non-ionogenically and/or condensed with aromatic rings. Alsocationic dyestuffs of the diphenylmethane, triphenylmethane, oxazine andthiazine series can be used as well as, finally, color salts of thearylazo and anthraquinone series having an external onium group, e.g.,an alkylammonium or cyclammonium group.

The amount of cationic color salt in the concentrated liquid dyepreparations according to this aspect of the in-vention is preferably lOto 30 percent. The particle size of the dyestuff is advantageously about0.5 to 5 as, if the particles are larger there is a danger of part ofthe dyestuff settling out of the dispersion in the form of a sediment.

The amount of salt contained in the dispersion should be at least highenough to ensure that the cationic dyestuff is substantially notdissolved. The minimal content required for the production ofconcentrated stable dispersions according to this aspect of theinvention depends, on the one hand, on the water solubility of thecationic dyestuff used and, on the other, on the dissolving propertiesof the salt used. In certain cases, a salt concentration of 3 percent issufficient. Preferably the salt content of the dyestuff dispersion isfrom about 5 to 25 percent. A higher salt content of the dye dispersionthan is necessary for attaining complete precipitation of the cationicdyestuff under practical conditions is generally to be avoided asotherwise difficulties with regard to the solubility of the dyepreparations can arise.

The amount of cationic or non-ionogenic stabilizer in the afore-saiddispersions is preferably 2.5 to 10 percent by weight of the totaldispersion.

The amount of water in the dispersions is generally between 40 andpercent by weight, preferably between 60 and 80 percent by weight.

Concentrated dispersions which prove to be particularly satisfactorycontain:

about 10-30 percent of cationic color salt,

5-25 percent of a water-soluble inorganic alkali, earth alkali, metal orammonium salt, particularly sodium chloride or magnesium chloride,

1-5 percent of an organic lower fatty acid, particularly acetic acid,

2.5- percent of a non-ionog enic stabilizer from the class of fattyalcohol polyglycol ethers and I 40-80 percent of water, all percentagesbeing calculated on the total weight of the dispersion.

The dispersions according to this aspect of the invention are produced,advantageously, by stirring the cationic color salt or cationicdyestuff, preferably in the form of a moist filter cake or also aspowder or aqueous solution or suspension, into the mixture of the othercomponents consisting essentially of an aqueous salt solution, acid andstabilizer and optionally further adjuvants, at room temperature orraised temperature of, preferably, not over 50C, using the usualtechnical mixing apparatus such as automatic stirrers, homogenizers orkneading apparatus, e.g., high velocity stirrers, turbomixers orkneaders. In many cases it is of advantage to add the main part of thestabilizer to the dispersion only after the other components have beenhomogenized. Moreover, it is often advantageous to comminute thecationic dyestuff mechanically in the same operation with the aid ofshearing stresses produced, for instance, by grinding elements such asquartz sand or glass pearls. The mixing operation is completed as soonas complete homogenization has been attained which is, usually, the caseafter 4 to 6 hours.

In contrast to pulverulent cationic dyestuffs, the dispersions accordingto the first aspect of the invention offer the great advantage that theycan be dissolved immediately and without the slightest difficulty by theaddition of cold or warm water. Compared with previously knownconcentrated solutions, they are distinguished by the followingadvantages: The dispersions according to the first aspect of theinvention do not tend to form sediments and can be stored for severalmonths. Above all, they are substantially unaffected by variations intemperature and the cationic dyestuff distributed but not dissolvedtherein does not form a sediment and also has no tendency to partiallycrystallize out. Inaddition, the dispersions according to the firstaspect of the invention are not hygroscopic and also do not tend to dryup which is always to be feared with 7 known concentrated solutions.

The dispersions according to the first aspect of the invention areready-for-use dye preparations. Diluted with water (advantageously in aratio of at least 1:10), they can be used directly as liquor for thedyeing and printing of organic materials such as leather, wool, silk,cellulose acetate, tanned cotton and, in particular, for the dyeing andprinting of polymeric and copolymeric acrylonitrile fiber material. Bystirring the preparations in dilute aqueous solutions containingsuitable thickeners, stable dyeing liquors or pastes are obtained whichare excellently suitable for use in continuous dyeing and printingprocesses.

The following non-limitative examples illustrate this invention aspectfurther. The temperatures are given therein in degrees Centigrade.

EXAMPLE 1 A solution is prepared of 45 g of sodium chloride, g of aceticacid and g of a fatty alcohol polyglycol ether, obtained by condensationof a mixture of fatty alcohols containing 11 18 carbon atoms with doublethe amount by weight of ethylene oxide in 300 g of water. 360 g of moistdyestuff filter cake composed of 120 g of dyestuff of the formula 24 gof sodium chloride and 216 g of water, are stirred Suitable acrylicfibers which can be dyed or printed using the above dye preparation are,in particular, polymeric and copolymeric, long chain acrylonitrile whichcontain'acid dye sites. Such fibers consist, e.g., of polyacrylonitrileof a polymerisation degree of about 35,000, containing about 150 mMcarboxyl groups and no sulfonic acid groups per 100 g fiber (COUR-TELLE, Courtaulds Ltd., Coventry, England). Other acrylic fibers usableaccording to the invention consist of polyacrylonitrile having a similardegree of polymerisation but about 40 to 50 mM sulfonic acid groups and15 to 20 mM carboxyl groups per 100 g of fiber (ORLON, E. I. Du Pont deNemours & Co., Wilmington, Del., USA), also ACRILAN, The ChemstrandCorp., Dekatur, Ala., USA, consisting of a copolymer from about percentacrylonitrile and about 15 percent vinyl acetate, or DRALON,Farbenfabriken Bayer, Dormagen, Germany, consisting of 85 percentacrylonitrile, about 5 10 percent vinyl acetate and about 10-15 percentvinyl pyridine.

Other equally good dye preparations are obtained in the same way andunder the same conditions as described in the above example if, insteadof the 30 g of fatty alcohol polyglycol ether, the following are used:25 g of a nonylphenol polyglycol ether the polyglycol ether chain ofwhich consists of 8 to 12 ethyleneoxy groups; 12 g of a condensationproduct of N-octadecyldiethylenetriamine and double the amount by weightof ethylene oxide; 20 g of the condensation product of oleic acid andethylene oxide (molecular ratio 117.5); 30 g of permethylatedN-octadecyl-diethylenetriamine having a polyglycol ether chaincontaining 15 to 20 ethyleneoxy groups.

If in the above example, the dyestuff component of the filter cake isreplaced by corresponding amounts of the cationic color salts given incolumn 2 of the following Table I and otherwise the procedure given inthe ex ample is followed, then dye preparations which are ready fordirect use and are stable on storing are also obtained.

Table lContinued Shadion polyut-rylnnitrilu Nmnlmr Dyosluil' fibers31).. .,r Cl Red.

| c2115 6 Q om 1\=N- N on; C10

\ crI2-c112-N CIIa CH3 40 H I Q Orange.

l C19 Ifii CH3 N l r-ro w EXAMPLE 4] a diameter of about 1.5 mm andthen, while stirring, 120 ofd st ffofth r 1 100 g of magnesium chloridecontaining crystal wag ye u e Ormu a ter, 2 g of concentratedhydrochloric acid and 0.1 g of fatty alcohol polyglycol ether (obtainedby condensa S 69 tion of a mixture of fatty alcohol containing ll to 18oclh carbon atoms with twice the amount of ethyleneoxide) O2NN=N N= I 9are dissolved in 60 g of water.

20 g of a dyestuff of the formula III CII:

V AL are added to this solution and the dyestuff suspension-N:NN(CzII5)2 ZnCl is stirred for 30 hours at room temperature. 200 g ofN water are then added and the glass pearls are separated CH1 from thefinely distributed, undissolved dyestuff by til- 40 tration of themilled goods over a copper sieve the mesh width of which is 0.5 mm. Inthis way, a homogeare added to the above-described solution and groundneous, stable, concentrated, liquid dye preparation is for 6 hours inthe Presence of Sand (g P The obtained. On pouring over the preparation1,000 times y Preparation so obtained is y Siabifi; the midis the amountof water and after addition of the auxiliasolved dyestuff does n t f rma dim even ries usual in dyeing, a liquor' is obtained which can beafter storing for a long time, has no tendency to crystald di f h d i fl ri or o ol meric lize out. On pouring over the preparation 1,000 timesl i il fib its amount of warm water, a liquor is obtained which I can beused direct for the dyeing of acrylic fibers from EXAMPLE 43 a g Q 8 gof the dye preparation produced according to exr Other dye preparationsare obtained if the procedure ample 1 and 40 g of 80 percent aceticacid, 50 g of sogiven in EXamPle 41 is followed instead of 100 g diumsulfate and 10 g of an addition product of 15 20 of magnesium chloride,65 g of sodium nitrate, 110 g equivalents f h l id to N octadecy| ofSodium Sulfate, 150 g of Sodium acetate, 40 g of P diethylenetriaminewhich has been quaternised with tassium sodium tartrate, 75 g of Sodiumchloride, 75 g dimethyl sulfate, are dissolved in 5,000 ml of water. ofzinc sulfate, 40 g of aluminum sulfate, g of potas- 100 g f l l i il yamo l w 42 are inn-0.. Sium tal'tfater g of Potassium Citrate, 65 g of flduced at 60, the liquor is heated within 10 minutes to Ilium Oxalate areUsedthen the temperature is raised by half a degree. per imi r y pr pare l in if 15 g f 60 minute until the boil is reached whereupon thematerial a locust bean flour thickener are added to the above solution.

EXAMPLE 42 g of sodium chloride, 5 g of formic acid and 30 g 65 is leftin the liquor at this temperature for 2 hours. The liquor is then cooledto 60 within 30 minutes. The material so dyed is then removed from thebath and rinsed with lukewarm and cold water.

Polyacrylonitrile yarn dyed a very even blue shade is '17 EXAMPLE 44Polyacrylonitrile fabric such as Orlon 42, is impregnated in a foulardat 40 with a liquor of the following composition:

20 g of the dye preparation obtained according to example 42 aredissolved in a thickener solution consisting of g of locust bean flourthickener and 885 ml of water, 60 g of acetic acid (80 percent) and 30 gof coconut oil fatty acid diethanolamide are then added.

The fabric which has been squeezed out to about 120 percent liquorcontent is steamed for 30 minutes at 102. The dyed goods are rinsed withwater, soapedand dried. Under these conditions a very level yellowdyeing is obtained. 1

If in the above example, instead of polyacrylonitrile.

fabric, cellulose acetate fabric is used and otherwise the proceduregiven in the example is followed, then a very level yellow dyeing isalso obtained.

The dye preparations described in the other examples produce dyeings ofsimilar quality by this process.

According to a second aspect of the invention stable dispersions ofwater-soluble anionic dyestuffs are provided which are particularlysuitable for the dyeing and printing of fiber materials consisting ofnatural and/or of synthetic polyamide and/or of natural or regeneratedcellulse. Y

Water-soluble anionic dyestuffs have hitherto been sold in the form offinely ground, more or less intensely dusty powders. Handling such dustydyestuff powders may easily lead to an annoying contamination of thesurroundings and to staining of the clothes and faces and hands of thepersonnel handling these dyestuff powders. Such handling, therefore,requires the use of I suitable protective devices,'such as ventilationequip-v ment. The contamination of the air by dyestuff particles canlead to a staining of other dyeable materials thus rendering useless forexample colorless textiles or textiles dyed in one shade. Moreover, veryfinely ground anionic dyestuffs tend very readily to form dyestufflumps'during storage in a moist atmosphere.

It is indeed possible to render dyestuffs dust-free by compressing orgranulating them, but the resulting preparations often have propertiesdiffering from those of the startingmaterials; Thu's, powderswhich'h'ave been compressed into granules, tablets or briquettes arefrequently difficult to dissolve or disperse. Therefore, in practice theaddition of wetting oils or of appreciable quantities of hygroscopicliquids, such as glycerine, is usually recommended. Both known methodsare unsatisfactory when applied alone, since, particularly in the caseof intensely dustry powders, the amount of dust given off, while beingreduced, is in no way eliminated and the formation of lumps is difficultto avoid. The, same also'applies to the mere moistening of anionicdyestuff powders with water. More recently, therefore, the known methodsmentioned above have only been used in combination with other measures.Thus, polyvalent aliphatic alcohols having hygroscopic properties andwater have been used; which, however,

does not guarantee constant satisfactory results; or the powders havebeen wetted with paraffin oil and subsequently rendered compact by theremoval of air under vacuum which requires special equipmentQThe knownbonding of the powder particles by moistening with steam in a turbulencezone leads only to a reduction but not to a satisfactory elimination ofthe dustiness of the powders.

In addition, it is often difficult to dissolve pulverulent anionicdyestuffs in water, since they are not easily wetted and form lumps whenwater is added, so that the preparation of dye liquors is oftendifficult and frequently very time-consuming.

This invention aspect provides for the first time, stable dispersions ofwater-soluble anionic dyestuffs of concentrated fluid consistency whichcan be produced in a simple manner and without modification of theirdyeing properties, which are easily soluble in water and which areessentially free of the above-mentioned disadvantages.

These novel stable dispersions have, as characteristic feature, acontent of, calculated on the total weight of the dispersion,

a. at least 10 percent and at most 60 percent by weight of water-solubleanionic dyestuff,

b. about 0.2 to 15 percent by weight of stabilizing agent, the balanceconsisting of c. water and, dissolved in the latter,

d. salt which is at least sparingly soluble in water and consists of theanion of an inorganic or organic monoor polybasic acid, and of thecation of an inorganic monoor polyacid base, the salt concentration inthe water being high enough to keep the water-soluble dyestuffsubstantially undissolved. This prevents a recrystallization of thedyestuff and resulting uncontrolled modifications in the viscos ity ofthe dispersion.

Here and in the following invention description as 7 well as in theappended claims the term anionic dyestuff designates a dyestuff moleculeconsisting of an anionic and a cationic moiety, the chromophoricstructure of the dyestuff being present in the anionic moiety, and thecationic moiety consisting of hydrogen, lithium, sodium, potassium orammonium.

A sparinglysoluble salt is a salt at least 1 part by weight of which issoluble in parts of water.

The anions of water-soluble salts usable according to the second aspectof the invention are primarily those from inorganic monoor polybasicmineral acids, e.g., from hydrochloric acid, hydrobromic acid, nitric orsulfuric acid. They can also be those from organic monoor polybasic,optionally substituted carboxylic acids; especially unsubstituted orhydroxyl-substituted lower aliphatic monodiand tricarboxylic acids;furthermore monocyclic-aromatic monocarboxylic acids. Suitable aniondonors are in the case of lower fatty acids, e.g., formic, acetic andglycolic acid; in the case of unsubstituted dicarboxylic acids, e.g.,oxalic acid, malonic, succinic, maleic, fumaric,glutaric and adipicacid; in the case of hydroxyl-substituted diand tricarboxylic acids,e.g., tartaric acid and citric acid. Suitable anions of mononucleararomatic carboxylic acids are for example those of benzoic acid,chlorobenzoic acid, methylbenzoic acid and salicylic acid.

Suitable cations of water-soluble salts usable in this aspect of theinvention are alkali metal ions such as sodium or potassium ions,ammonium ions, mono-, di-

ferred. Examples of suitable inorganic salts are, in particular, theneutral alkali metal, ammonium or alkaline earth metal salts of strong,inorganic monoor polybasic acids such as sodium, potassium and ammoniumchloride; magnesium, calcium or zinc chloride; sodium, potassium andammonium bromide; sodium, potassium and ammonium nitrate; sodium,potassium and ammonium sulfate; sodium, potassium and ammoniumphosphate; or mixtures thereof; examples of suitable salts of organicacids are, in particular, the alkali metal salts of lower fatty acids,especially sodium and potassium ace tate, citrate and tartrate.Water-soluble neutral alkali metal or ammonium salts of strong inorganicmonoor polybasic acids, especially sodium chloride, are particularlypreferred.

Examples of suitable water-soluble anionic dyestuffs which can be usedin their dispersions according to the invention are acid wool dyestuffsas well as reactive and substantive dyestuffs, such as the alkali metalor ammonium salts of sulfonic or carboxylic acid dyestuffs or of 2:]metal complex dyestuffs, namely metal-free or metallized monoazo-,disazo- (including formazane) or polyazo-dyestuffs, and the chromium,cobalt, nickel and copper complexes thereof; and metallized monoazodyestuffs, especially those having two axo dyestuff molecules bound toone coordinatively hexavalent heavy metal atom; as well asanthraquinone, nitro and also phthalocyanine dyestuffs. After-chrornabledyestuffs, especially afterchromable azo dyestuffs, are also suitable.Suitable reactive dyestuffs are those which are capable of reacting withwool or cotton fibers, especially those which are azo, anthraquinone orphthalocyanine dyestuffs.

3 Stabilizing agents contained in the dispersions according to thesecond aspect of the invention are preferably anionic and/ornon-ionogenic.

Examples of suitable anionic stabilizing agents are:

l. the salts designated as soaps, namely the sodium, potassium,ammonium, N-alkyl-, N-hydroxyalkyl-, N- alkoxyalkylorN-cyclohexylammonium, or the hydrazinium and morpholinium salts of fattyacids having to 20 carbon atoms, such as lauric, palmitic, stearic oroleic acid; e.g.,- sodium laurate; sodium stearate;

2. sulfated primary or secondary, purely aliphatic alcohols having eightto 18 carbon atoms in the alkyl chain, e.g., sodium lauryl-sulfate,sodium a-methyl stearyl-sulfate, sodium tridecyl-sulfate, sodiumoleylsulfate, potassium stearyl-sulfate or the sodium salt of coconutfatty alcohol-sulfate;

3. sulfated unsaturated higher fatty acids or fatty acid esters, such asoleic acid, elaidic acid or ricinoleic acid, or the lower alkyl estersthereof, e.g., the ethyl, propyl or butyl esters, and the oilscontaining such fatty acids, such as olive oil, castor oil, rape oil,etc.; e.g., disodium heptadecyl carboxylate sulfate;

4. sulfated ethyleneoxy adducts, such as sulfated addition products of lto 10 moles of ethylene oxide with fatty acid amides, mercaptans oramines, especially, however, with fatty acids, aliphatic alcohols oralkyl phenols having eight to 20 carbon atoms in the alkyl chain, e.g.,with stearic acid, oleic acid, lauryl alcohol, myristyl alcohol, stearylalcohol, oleyl alcohol, octylphenol or nonylphenol e.g., sodium salt ofsulfated lauryl alcohol triglycole ther or sodium octylphenyldeca-ethylene glycol-sulfate;

5. the sulfates of N-acylated alkanolamines, e.g., the sulfated amidesof caprylic, pelargonic, capric, lauric,

myristic or stearic acid, or of lower fatty acids substituted byalkylphenoxy groups, such as octylor nonylphenoxy acetic acid withmonoor bis-hydroxyalkylamines such as B-hydroxyethyl-amine,y-hydroxypropyl-amine, B,-y-dihydroxypropyl-amine, bis-(B-hydroxyethyl)-amine, or with N-alkyl-N-hydroxyalkylamines such asN-methyl, or N-ethyl-N-(B- hydroxyethyl)-amine; e.g.,sodium salt ofsulfated nonylphenoxy acetic acidbisfi-hydroxyethylamide;

6'. sulfated esterified polyoxy compounds, e.g., sulfated, partiallyesterified polyvalent alcohols, such as the sodium salt of the sulfatedmonoglyceride of palmitic acid;

7. primary and secondary alkyl-sulfonates, the alkyl chain of whichcontains 10 to 20 carbon atoms, e.g., sodium dodecylsulfonate, sodiumhexadecane-sulfonate- 8 sodium stearyl-sulfonate;

8. alkyl-aryl sulfonates such as alkali metal alkylbenzene sulfonateswith straight or branched alkyl chain of at least 7 carbon atoms, e.g.,sodium dodecylbenzene sulfonate, l,3,5,7-tetramethyl-octylbenzenesulfonate, sodium octadecylbenzene sulfonate; or such as alkylnaphthalene sulfonates, e.g., sodium-lisopropyl-naphthalene-2-sulfonate,sodium dibutylnaphthalene sulfonate;

9. alkali metal sulfonates of polycarboxylic acid esters, e.g., sodiumdioctyl-sulfosuccinate, sodium dihexyl-sulfophthalate.

Instead of the sulfates, esters with other polyvalent mineral acids,e.g., phosphates, can also be used;

10. condensation products of aryl sulfonic acids with formaldeyhyde,such as alkali metal dinaphthylmethane sulfonates, e.g., the disodiumsalt of di-( 6-sulfonaphthyl-2 )-methane.

Examples of suitable non-ionogenic stabilizing agents are:

ll. addition products of alkylene oxides, especially from ethyleneoxide, with higher fatty acids, fatty acid amides, aliphatic alcohols,mercaptans or amines, with alkyl phenols or alkyl thiophenols, the alkylradicals of which have at least seven carbon atoms. Preferred arepolyglycol-mono-alkyl phenyl ethers with 2 to 20 optionally substitutedglycol units, the alkyl group of which has eight to 12 carbon atoms,such as tri-(l,2- propylene-glycol)-mono-nonylphenyl ether,pentaethylene-glycol-mono-octylphenyl) ether ordecaethyleneglycol-mono-nonylphenyl ether;

12. esters of polyalcohols, in particular monoglycerides-of fatty acidswith 12 to 18 carbon atoms, e.g., the 'monoglycerides of lauric, stearicor oleic acid;

13. N-acylated alkanolamines of the same type given for the sulfates ofthese compounds, thus e.g., the N,N- bis (m-hydroxyalkyD-amides of themixture of acids known by the generic term coconut oil fatty acids,primarily N,N-bis(/3-hydroxy-ethyl)- or N,N-bis('yhydroxypropyl)-amides,also the addition products of ethylene oxide with these N-acylatedalkanol amines;

14. the reaction products of higher fatty acids with an alkanol amine,whereby the molar ratio of alkanol amine to fatty acid is greater than1, e.g., 2. As fatty acids those having eight to 18 carbon atoms as wellas the mixtures designated as coconut oil fatty acids are particularlysuitable, and diethanol amine is a particularly suitable alkanol amine.Substances of this sort are described in US. Pat. No. 2,089,212. Thesecompounds are not uniform in nature and some have cationiccharacteristics.

The technically available Stabilizing agents of the classes named areusually not uniform products, but rather mixtures of homologues of thecompounds mentioned.

Preferred are anionic and/or non-ionogenic stabilizing agents which arecondensation products of aryl sulfonic acids andformaldehyde,alkali-metal sulfates of higher alkanols or additionproducts of ethylene oxide with higher aliphatic alcohols oralkylphenols as defined under 10, 2 and 11, supra.

As other auxiliaries, the dispersions according to the second aspect ofthis invention can contain up to about 5 percent by weight of organicacid such as formic or acetic acid; up to about percent by weight ofthickeners such as alginates, locust bean flour, alkyl celluloses ofcrystal gum; up to 1 percent by weight of antifoaming agents such ashigher fatty alcohols, higher molecular fatty acid esters or siliconeoils; up to about 2 percent of wetting agents such as alkyl naphthalenesulfonates and up to about 10 percent by weight of detergent agents suchas fatty acid condensation products, or textile finishing agents, e.g.,textilesofteners, antistatic agents and antisoiling agents such asquaternary ammonium compounds or fatty acid condensation products, forexample, condensation products of fatty acids with polyoxy compounds.

The amount of anionic dyestuff in the dispersions should be as high aspossible, being preferably from 30 to 60 percent by weight of the totaldispersion. The upper limit is determined by the fact that thepreparations should still be flowable.

The amount of salt contained in the dispersion should always be highenough to ensure that the water-soluble anionic dyestuff issubstantially undissolved. The minimum content required for theproduction of stable dispersions depends, on the one hand, on thewatersolubility'of the anionic dyestuff used and, on the-other hand, onthe solvatation properties of the salt used. In

certain cases, a slat concentration of 3 percent is sufficient.Preferably, the salt content of the preparations according to thisaspect of the invention is from about 5 to percent. A high saltconcentration can improve the rheological properties of the preparation,which is of particular importance when the preparation is stored for aprolonged time; on the other hand, however, difficulties with regard to.the solubility of the preparations can arise when they are to bediluted with water. The optimal salt concentration must, therefore, bedetermined empirically in each case. I

The amount of stabilizing agent in these dispersions is preferably about0.5 to 10 percent of their weight.

The amount of water in the stable dispersions is generally between 40and 85 percent, preferably between and 70 percent of their weight.

The dispersions according to the second aspect of the invention areproduced, advantageously, by stirring the anionic dyestuff, preferablyin the form of a moist filter cake or also as powder or aqueous solutionor suspension, into the mixture of the other components consisting of anaqueous salt solution, the stabilizing agent and optionally otherauxiliaries, at room temperature, preferably not above 50C, using theusual technical mixing apparatus, such as stirring equipment,homogenizers or kneading apparatus, e.g. high velocity stirrers,turbomixers or kneaders. In many cases it is of advantage to add themain part of the stabilizing agent to the preparation after the othercomponents have been homogenized. If often also proves advantageous tosimultaneously distribute the anionic dyestuff mechanically, usingshearing forces, e.g., grinding particles such as quartz sand or glassbeads'The mixing operation is concluded as soon as completehomogenization has been attained which is, usually, after 4 to 6 hours.

In contrast to pulverulent anionic dyestuffs, their dispersionsaccording to the invention have, above all, the great advantage thatthey can be dissolved immediately by the addition of cold or warm waterwithout the slightest difficulty. The afore-said dispersions can bestored for several months. Above all, they are substantially unaffectedby variations in temperature and the dyestuff distributed but notdissolved therein does not form a sediment or can be easilyhomogeneously distributed by simple stirring or shaking; it also has notendency to crystallize.

The dispersions of this aspect of the invention are ready-for-use dyepreparations. Depending on the type of anionic dyestuff therein, theycan be used either diluted with water, advantageously in a weight ratioof at least 1:10, or directly, as liquor for the dyeing and printing oforganic materials, in particular fiber material consisting of naturaland regenerated cellulose, natural and synthetic polyamide, especiallywool and cotton. By stirring the preparations in water or suitableEXAMPLE 45 While stirring, 900 g of a moist filter cake containing 500 gof the dyestuff of the formula are added to a solution consisting of 800ml of water, 200 g of sodium chloride and 15 g of the condensationproduct of 2 parts of naphthalene-Z-sulfonic acid and 1 part offormaldehyde, and then homogenized for 3 hours. The dark redconcentrated dyeing preparation obtained in this manner is easilyflowable, stable to storage and ready for use. By stirring thepreparation in ten times the amount of aqueous thickening agent andadding the auxiliaries usual in printing with reactive dyestuffs, aprinting paste for the printing of natural or regenerated cellulosefibers is obtained.

Other dye preparations having similar properties are obtained when theabove example is followed, but the 200 g of sodium chloride are replacedby 180 g of potassium chloride, 200 g of ammonium chloride, [00 g ofsodium nitrate, g of sodium sulfate, 300 g of so- I Similar dyepreparations are obtained by adding 150 the anionic reactive dyestuffsgiven in column 2 of the g of sodium alginate thickener and 5 g ofsilicone oil to following Table ll and otherwise the procedure given inthe above solution. the example is followed, then dye preparations whichIf in the above example, the dyestuff component of are ready for use andare stable to storage are also obthe filter cake is replaced bycorresponding amounts of 5 tained.

TABLE II Shade on natural and l'vgvnvmtml Example cellulose numberDyestufl lilim's 46 CH3 Gruouish 01 yellow. N=C HOa S l I CN=N N N ll I:HO3S NHC C 1 01 CH 01 47 Cl Rnddish yellow. 0 S 03H S 0 11 i N=NNHC CNH1 N CH; HOaS l S 03H 48 E) ITIHZ Blue.

( U -s 03H ll 1 0 N11 S 0 11 S 0311 l Nil-(If (IJ-NH- N\ N 49 OH NH-CQCH= (ID-CH; Orange.

| S 0 H S 0 H l S 03H 50 I I 01 Cl Turquoise.

(HO3S)3CuPh-S OZNH L o-c NH-C N (whcrtin Culh designates the copperphthalocyaninc radical).

51 |O( )u (I) Bordeaux.

Hois- 11=N Table ll-Continued Shade on natural and regenerated Examplecellulose number Dyestufi fibers 52 S 02-0113 Blue.

s 03H N=- l I l Cu 01 CH3 HOaS- I l N N 53 S 03H I (')H Orange.

H O;S- N C 0- V I Q 1 CH S 03H S Og-CH:

54 S 0311 Greenish OH yellow. S 03H CN N=N-C i S OaH C=N NH I (g CH3EXAMPLE 55 yellow shades.

75 g of sodium chloride and 5 g of a fatty'alcohol polyglycol etherobtained by condensing a mixture of fatty alcohols having 1 l to 18carbon atoms with twice the amount of ethylene oxide, are dissolved in500 ml of water. 360 g of moist dyestuff filter cake, consisting of 12Qg of dyestuff of the formula l l CH3 H .9 3 V... "M; a

24 g of sodium chloride and 216 ml of water are added to this solutionwhile stirring at room temperature and the mixture is homogenized for 5hours. The dye preparation thus obtained is very stable; the undissolveddyestuff does not form a sediment and, even after storing for a longtime, has no tendency to crystallize. By pouring 500 times the amount ofwarm water over the preparation, a liquor is obtained which can be useddirectly for the dyeing of cellulose fibers from a long bath in Otherdye preparations having similar properties are obtained when theprocedure given in the above example is followed, but the g of sodiumchloride are replaced by 180 g of potassium chloride, of ammoniumchloride, 65 g of sodium nitrate, l 10 g of sodium sulfate, g of sodiumacetate, 40 g of potassium so- TABLE lll Example Shade on cellulose No,Dyesluff fibers l-amino-8-hydroxynaphthalene-3,6-disulfonic acid ,flk

aniline 56 Benzidine Black.

m-phenylenediamine 57 ng-khxd ry z nzw acid la hthy a i -Vm n hxr napytabnwf9 ic acid D 58 Aniline l-aminonaphthalene-7-sulfonic acidl-aminonaphthalene7-sulfonic acid 2-amino-8- Grey.

hydroxynaphthalcne-6-sulfonic acid.

59 l-aminobenzene-3'sulfonic acidl-aminonaphthalene-7-sulfonic acidl-amino-Z-methoxy- Blue-green.

'* naphthalene-6-sulfonic acid [2-amino-5-hydroxy-naphthalene-7-sulfonicacid Laminobenzene-S- sulfonic acid]. 7

2-amino-5-hydroxynaphthalene-7-sulfonic acid 2-amino-5-nitrobenzoic acidNavy b lue 60 Dianisidine after-coppered.

2-naphthol-6-sulfonic acid salicylic acid 61 Benzidine Brown.

[resorcinol 2-aminophenol-4-sulfonic acid] copper complex.

6 2. Z-naphthylamine-4,8-disulfonic acid Nacetyl-m-phenylenediamine(phosgenated). Yellow.

63. g anisidi q i sulfgnic acid 3 5,5'-dihydroxy-7,7'-disulfonic acid2,2'-dinaphthylurea copper complex Violet.

64 p-aminosalicylic acid laminQ-Z-methoxynaphthalene-6-sulfonic acid2-acetoacetylamino-6- Green.

naphthol-8-sulfonic acid anthranilic acid copper complex.

65 4-aminoazobenzene-3,4-disulfonic acid 2-[4'anilino6'-p-sulfoanilino2-triazinylamino]-5-hydroxy-7- Brilliant red.

' sulfonic acid.

EXAMPLE 66 EXAMPLE 67 60 g of sodium chloride, g of 80 percent aceticacid, g of a polyglycol ether, obtained by condensation of a mixture offatty alcohols having 11 to 18 carbon atoms with twice the amount ofethylene oxide and 10 g of a wetting agent consisting of alkylnaphthalene sulfonates are dissolved in 410 ml of water. 200 g of glassbeads having a diameter of about 1.5 mm. and then 'while stirring, 120 gof the dried dyestuff of the formula HOW are added to this solution andthe dyestufi suspension is stirred for 30 hours at room temperature. Theglass beads are then separated from the finely distributed, undissolveddyestuff by filtration of the milled goods over a copper sieve the meshwidth of which is 0.5 mm. In this way, a homogeneous, stable,concentrated, liquid dye preparation is obtained. By pouring 500 timesthe amount of water over the preparation and after adding auxiliariesusual in dyeing, a liquor is obtained which can be used directly for thedyeing of wool in red shades.

Other dye preparations are obtained when the procedure given in theabove example is followed, but the 60 g of sodium chloride are replacedby 100 g of potassium chloride or 80 g of sodium sulfate.

While stirring, 360 g of moist filtercake consisting of g of the anionicdyestufi' of the formula O- I l Cr Na HzNOgS N COO I usual in dying, aliquid is obtained which can be used directly for the dyeing of wool andsynthetic polyamide.

Similar dye preparations are obtained by adding 3 g of silicone oil and20 g of a fatty acid condensation product to the above solution.

If in the above example, the dyestuff component of the filter cake isreplaced by corresponding amounts of the dyestuffs given in column 2 ofthe following Table IV and otherwise the procedure given in the exampleis followed, then dye preparations which are ready for use and arestable to storage are also obtained.

' M Table IV Continued Example Shgdo onl wool t v number Dyestufi' gglyztiiiidia OH HO Black alterchromed.

HO3S- N=N EXAMPLE 86 from the group consisting of hydrochloric acid,sulg of the dye preparation produced according to Example 45 (withoutthickener) are dissolved in 3,000 ml of water and then 60 g of trisodiumphosphate are added. 100 g of cotton are introduced at 40 and thetemperature is raised within 30 minutes to 80, while simultaneouslyadding sodium chloride in such an amount that by completion of theaddition there are i 150 g per liter. Dyeing is performed at thistemperature .for one hour. Then the dyed goods are soaped for.30

minutes at the boil, rinsed and dried.

A very level red dyeing is obtained.

EXAMPLE 87 conut oil fatty acid diethanol amide are then added to thesolution.

The fabric, squeezed to about 120 percent pick-up, is steamed at 102 for30 minutes. The dyed goods are rinsed with water, soaped and dried.Under these conditions a very level red wool dyeing is obtained.

What is claimed is:

l. A stable dispersion of a water-soluble cationic dyestuff consistingessentially of a. from 10 percent to 30 percent by weight of awater-soluble cationic color salt,

b. from about 1 to 5% by weight of an acid selected percent by weight ofthe dispersion.

phuric acid, formic acid and acetic acid, 0. from 0.5 to 15 percent byweight of a cationic or non-ionic stabilizer, all percentages beingcalculated on the total weight of the dispersion, the balance of thedispersion consisting essentially of d. water and, dissolved in thewater, e. at least 5 percent by weight, based on the total weight of thedispersion, of a water-soluble alkali metal, alkaline earth metal orammonium salt of i. an inorganic acid selected from the group consistingof hydrochloric acid, nitric acid and sulphuric acid, or

ii. an organic acid selected from the group consisting of loweraliphatic mono-, diand tricarboxylic acids, hydroxyl substituted loweraliphatic mono-, di and tricarboxylic acids and mononuclear aromaticmonocarboxylic acids.

2. The dispersion as defined in claim 1, wherein the acid defined under(b) is formic or acetic acid.

3. The dispersion as defined in claim 2, wherein the water-soluble saltis sodium chloride, the acid is acetic acid and the stabilizer is afatty alcohol polyglycol ether.

4. The dispersion as defined in claim 2, wherein the water-soluble saltis magnesium chloride, the acid is acetic acid and the stabilizer is afatty alcohol polyglycol ether.

5. The dispersion as defined in claim 1, wherein the stabilizer is anon-ionic stabilizer.

6. The dispersion as defined in claim 1, wherein the content of saltcomponent (e) in the dispersion is 5-25

2. The dispersion as defined in claim 1, wherein the acid defined under(b) is formic or acetic acid.
 3. The dispersion as defined in claim 2,wherein the water-soluble salt is sodium chloride, the acid is aceticacid and the stabilizer is a fatty alcohol polyglycol ether.
 4. Thedispersion as defined in claim 2, wherein the water-soluble salt ismagnesium chloride, the acid is acetic acid and the stabilizer is afatty alcohol polyglycol ether.
 5. The dispersion as defined in claim 1,wherein the stabilizer is a non-ionic stabilizer.
 6. The dispersion asdefined in claim 1, wherein the content of salt component (e) in thedispersion is 5-25 percent by weight of the dispersion.